#include <ctype.h>
#include <stdio.h>
#include <string.h>
int main() {
  char s[101], t[201];
  int p = 0;
  scanf("%s", s);
  for (int i = 0; i < strlen(s); i++) {
    if (tolower(s[i]) == 'a' || tolower(s[i]) == 'o' || tolower(s[i]) == 'y' ||
        tolower(s[i]) == 'e' || tolower(s[i]) == 'u' || tolower(s[i]) == 'i')
      continue;
    t[p++] = '.';
    t[p++] = tolower(s[i]);
  }
  t[p] = '\0';
  printf("%s\n", t);
  return 0;
}